Glove box attachment



Feb. 13, 1962 H. L. BUTTS GLOVE BOX ATTACHMENT Filed March 51, 1960 R O m E V m can if nits 3,020,647 GLOVE BOX ATTACHMENT Harvey L. Butts, Kennewick, Wash, assignor to the United States of America as represented by the United States Atomic Energy Commission Filed Mar. 31, 1960, Ser. No. 19,136 2 Claims. (Cl. 34-92) This invention relates to an attachment for a glove box that will protect the glove and keep it out of the way during evacuation of the glove box for purging purposes.

In order to work with pyrophoric radioactive materials it is necessary to exclude oxygen from the atmosphere of the work area. Glove boxes, usually employed for this purpose, enable the operator to perform various operations in nonoxidizing atmospheres such as argon or helium.

In the past, glove box atmospheres have been purged of oxygen by flushing the glove box with the inert gas desired. Under these conditions it is diificult to remove oxygen etficiently since large quantities of inert gas are required to dilute the oxygen content of the atmosphere to sufficiently low levels. Such a practice is undesirable when the inert gas is relatively expensive, or when radioactive dusts must be carefully filtered from all of the gas circulated through a glove box. For example, a serious health hazard exists where plutonium is involved since this element is not only pyrophoric but also highly toxic. if ingested, or breathed into the lungs, plutonium oxide is readily transferred by the blood stream to bone tissue. There the high alpha activity of plutonium causes severe damage to blood-manufacturing cells.

Another method which has been used for changing glove box atmospheres involves repeated partial evacuations. This method again requires large volumes of inert gas which must be filtered when removed from the glove box, and also causes additional health hazards from leaks developed by stretching the unprotected glove.

The device of this invention permits an efficient and positive removal of oxygen from glove box atmospheres through evacuation. This invention provides a means for creating an inert atmosphere with a minimum of inert gas. This invention also provides means for simultaneously, yet independently, evacuating a glove box and the attached glove without damage to the glove.

The foregoing and other objects and advantages of the invention will become apparent from a consideration of the following specification and the accompanying drawing, wherein:

FIG. 1 is an end view of the novel protective attachment of the present invention for a glove box;

FIG. 2 is a sectional view taken on the line 2-2 of FIG. 1 and showing how the protective attachment is connected to a glove and to the glove box;

FIG. 3 is an elevation of a valve plate forming part of the protective attachment;

FIG. 4 is a sectional view taken on line 4-4 of FIG. 1 and showing the construction of a handle for manipulating the valve plate; and

FIG. 5 is a sectional view taken on the line 5--5 of FIG. 4.

As shown in F168. 1 and 2, the novel glove box attachment comprises a housing 2, having registered openings 4 and 6, and a valve plate 8, positioned by knob 10. The housing 2 has opposed walls 12 and 14 separated by a ring 16 which is welded to the walls 12 and 14 as at 17 and forms a peripheral seal. An externally grooved rim 13 is welded to the wall 14 in registry with opening 4 and provides means for attachment of a glove 2%. Valve plate 8 seats against O-ring 22 positioned in a groove on the wall 12 during evacuation of a glove box 26, which is sealed to the wall 12 by welds 28. Valve 24 is threaded into the wall 12.

In FIG. 4 a bushing 30 is threaded into the housing wall 14 and sealed with an O-ring seal 32. Shaft 34, located in bushing 30, has a square end 36 which loosely fits a square hole 37 in valve plate 8. Collar 38 on shaft 34 keeps the square end 36 in the hole 37. Q-ring seal 40 provides a vacuum seal between the shaft 34 and the bushing 30. As shown in FIGS. 4 and 5, a split-ring collar 42, which is secured to the shaft 34 by tightening screw 44, slidably mounts a pin 46, which has one end secured to the knob and the other end insertable in two indexing holes in the bushing 30. One of the holes, designated 48, is seen in FIG. 4 as receiving the pin 46, and the other hole is not shown but will be understood as being angularly displaced from the hole 48 about the shaft 34. Knob 10 is slidably mounted on shaft 34 and is biased toward the bushing 30 by spring 50, which is retrained by washer 52, which is secured to shaft 34 by screw 54-. As the knob 10 is pulled outwardly, pin 46 is disengaged from indexing hole 48 and by remaining in collar 42 gives positive control in shifting the valve plate 8 within the housing 2 between the dashed position of FIG. 1 in which the valve plate covers the housing openings 4 and 6 and dash-dot position in which the valve plate is to one side of these openings.

In operation, the valve plate 8 is positioned over the opening 6 in the glove box which is then evacuated. During this step the valve plate is pressed against the O-ring seal 22 by atmospheric pressure, thus sealing the glove box. The housing 2 is evacuated at the same time through the valve 24 in the first wall of the housing; this evacuates the glove, also. During evacuation of the housing and glove, the glove is supported by the valve plate 8 and at the same time forms a seal between the atmosphere and the inside of the housing 2. Little stress is applied to the glove since the clearance is small between the valve plate and the wall 14 of the housing.

When the evacuation step is completed, the box is filled with inert gas to about atmospheric pressure. The housing 2 and glove 20 are filled with inert gas through the valve 24 used for evacuation. The valve plate 8 is then positioned to one side of the opening 6 and the glove is inserted into the glove box, ready for use. A slight negative pressure is maintained in the glove box to minimize the spread of hazardous materials in the event that a leak should develop in the glove or glove box. The housing with attached glove continue to seal out the atmosphere when the glove box is in normal operation.

It is understood that the invention is not to be limited by the details given herein, but that it may be modified within the scope of the appended claims.

What is claimed is:

1. In a glove box assembly comprising a glove, and a box having an opening through which the glove may be inserted, the combination therewith of a housing comprising a first wall sealed to the box and having an opening therein coincident with the opening in the box, a second wall parallel to the first wall and having an opening aligned with the opening in the box, means for attaching the glove over the opening in the second wall, a valve plate positioned within the housing which is suificiently long to permit pivotal retraction of said valve plate out of overlapping relationship with said opening, external means for pivoting the valve plate, an O-ring gasket positioned around the opening in the first wall to seal the valve plate to the first wall during evacuation of the box, a peripheral seal holding the first and second walls in a spaced-apart relationship to permit sliding movement of said valve plate, and means for evacuating said box and said housing with glove attached.

2. In a glove box assembly comprising a glove, and a box having an opening through which the glove may be inserted, the combination therewith of a housing sealed l atented Feb. 13, .1962

tered opening in the housing, and valve means for evacuation of the housing during evacuation of the box.

References Cited in the file of this patent relationship between the valve plate'and the inner regis- 10 2,949,275

UNITED STATES PATENTS Rogers et al. Sept. 4, 1917 Renehan Mar. 8, 1927 Bloomer et a1 Dec. 2, 1958 Pro Aug. 16, 1960 

